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US 12/Old Highway 9 Roundabout Pre-design Study

Planning study news

Thank you for participating in the US 12/Old Highway 9 Roundabout Pre-design study. The pre-design is complete. The project has moved to a WSDOT design office to begin the design phase.

Timeline
January - June 2025
Status
Complete
Budget
$103,625

Purpose

This pre-design sought feedback on a roundabout concept for the intersection of US 12 and Old Highway 9 in southwest Thurston County.

In April 2025, WSDOT met with local agencies. In May 2025, WSDOT conducted an online open house. The purpose of this engagement was to gather feedback about the roundabout concept. The community engagement summary (PDF 1.05MB) is available for review.

WSDOT reviews intersections on the state highway system for safety. We look for the locations with the highest risk for severe crashes. That process identified the US 12/Old Highway 9 intersection for safety improvements. The recommended safety improvement is a single-lane roundabout. The pre-design process will find the best possible concept to proceed to the design phase.

The project location at US 12 and Old Highway 9 is located in Grand Mound, in the southwestern corner of Thurston County.